Narrative:

Aircraft was cleared to logen intersection when first officer was absent from cockpit for personal biological reasons. Aircraft was level at FL240. First officer returned to cockpit and was informed of clearance direct to logen. Upon inspection of latitude/longitude of waypoint that aircraft was proceeding to, determined wrong waypoint selected. At that time, ATC issued descent to FL200. Altitude set, and annunciated, in altitude selector. First officer commenced verifying and inputting proper waypoint latitude/longitude. At FL210, the required '1000 ft to go, out of FL210 for FL200' was made by the first officer and 'rogered' by the captain. Before the finalization of the correct waypoint was completed, a radical pull-up was initiated by the captain. When questioned why, the captain stated that the aircraft autoplt failed to capture the set altitude, FL200. The aircraft descended below FL200 by 400-450 ft before returning to the cleared altitude. For unknown reasons, the aircraft did not level off. After, the aircraft was leveled off manually, (the autoplt was disconnected by captain during his attempt to re-level the aircraft) and the altitude set knob was reset to FL200. 2 flight attendants were shaken up and sustained minor injuries that were brought to the attention of the flight crew within 10 mins of the incident. No ATC comments were made about altitude bust.

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Original NASA ASRS Text

Title: CAPT OF A L1011 OVERSHOT DSCNT XING RESTR ALT AND MADE SUCH AN ABRUPT CORRECTION THAT 2 FLT ATTENDANTS WERE INJURED. IN ADDITION, SINCE THE WRONG WAYPOINT HAD BEEN ENTERED INTO THE FMC, RPTR WAS NOT ON THE PRESCRIBED STAR ARR TRACK.

Narrative: ACFT WAS CLRED TO LOGEN INTXN WHEN FO WAS ABSENT FROM COCKPIT FOR PERSONAL BIOLOGICAL REASONS. ACFT WAS LEVEL AT FL240. FO RETURNED TO COCKPIT AND WAS INFORMED OF CLRNC DIRECT TO LOGEN. UPON INSPECTION OF LATITUDE/LONGITUDE OF WAYPOINT THAT ACFT WAS PROCEEDING TO, DETERMINED WRONG WAYPOINT SELECTED. AT THAT TIME, ATC ISSUED DSCNT TO FL200. ALT SET, AND ANNUNCIATED, IN ALT SELECTOR. FO COMMENCED VERIFYING AND INPUTTING PROPER WAYPOINT LATITUDE/LONGITUDE. AT FL210, THE REQUIRED '1000 FT TO GO, OUT OF FL210 FOR FL200' WAS MADE BY THE FO AND 'ROGERED' BY THE CAPT. BEFORE THE FINALIZATION OF THE CORRECT WAYPOINT WAS COMPLETED, A RADICAL PULL-UP WAS INITIATED BY THE CAPT. WHEN QUESTIONED WHY, THE CAPT STATED THAT THE ACFT AUTOPLT FAILED TO CAPTURE THE SET ALT, FL200. THE ACFT DSNDED BELOW FL200 BY 400-450 FT BEFORE RETURNING TO THE CLRED ALT. FOR UNKNOWN REASONS, THE ACFT DID NOT LEVEL OFF. AFTER, THE ACFT WAS LEVELED OFF MANUALLY, (THE AUTOPLT WAS DISCONNECTED BY CAPT DURING HIS ATTEMPT TO RE-LEVEL THE ACFT) AND THE ALT SET KNOB WAS RESET TO FL200. 2 FLT ATTENDANTS WERE SHAKEN UP AND SUSTAINED MINOR INJURIES THAT WERE BROUGHT TO THE ATTN OF THE FLC WITHIN 10 MINS OF THE INCIDENT. NO ATC COMMENTS WERE MADE ABOUT ALT BUST.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.